Title
Long-term limb immobilization modulates inhibition-related electrophysiological brain activity.
Abstract
The effect of long-term immobilization on the motor system has been described during motor preparation, imagination or execution, when the movement has to be performed. But, what happens when the movement has to be suppressed? Does long-term limb immobilization modulate physiological responses underlying motor inhibition? Event-related potentials (ERPs) were recorded in healthy participants performing a Go/Nogo task, either with both hands free to respond (T1/T4: before/after the immobilization) or when left-hand movements were prevented by a cast (T2: as soon as the cast was positioned; T3: after one week of immobilization). In the right (control) side, N140, N2, and P3 components showed the expected greater amplitude in Nogo than in Go trials, irrespective of the timepoint. On the contrary, in the left (manipulated) side, each component of the ERP responses to Nogo trials showed specific differences across timepoints, suggesting that the inhibition-related EEG activity is significantly reduced by the presence of the cast and the duration of the immobilization. Furthermore, inhibition-related theta band activity to Nogo stimuli decreased at post-immobilization blocked session (T3-blocked). Altogether these findings can be interpreted as a consequence of the plastic changes induced by the immobilization, as also demonstrated by the cast-related corticospinal excitability modulation (investigated by using TMS) and by the decreased beta band in response to Go and Nogo trials. Thus, only if we are free to move, then inhibitory responses are fully implemented. After one week of immobilization, the amount of inhibition necessary to block the movement is lower and, consequently, inhibitory-related responses are reduced.
Year
DOI
Venue
2020
10.1016/j.neuroimage.2020.116911
NeuroImage
Keywords
DocType
Volume
Long-lasting immobilization,Motor inhibition related N2–P3 complex,EEG,Single-pulse TMS,Theta band,Beta band
Journal
218
ISSN
Citations 
PageRank 
1053-8119
0
0.34
References 
Authors
0
6
Name
Order
Citations
PageRank
Valentina Bruno100.34
Irene Ronga201.35
Carlotta Fossataro301.01
Mattia Galigani400.34
Katiuscia Sacco5806.20
Francesca Garbarini632.15